Abstract
Full preservation of ancient meandering channels is uncommon: most preserved architectural elements are fragmented due to later erosion and cutting of channels and bars. This makes it challenging to relate preserved architectural elements to the original dimensions at the time of sedimentation. Quantitative information on the three-dimensional geometry and composition
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of these basic building blocks of reservoirs and aquifers formed by meandering systems is essential for exploration and production purposes and potentially an invaluable source of information about ancient climate. In this thesis the relation between the morphodynamics of meandering rivers and the resulting stratigraphic architecture is explored and quantified in three dimensions. This led to a scale-independent inverse relation that uses stratigraphy to predict the original meandering river dimensions that is of considerable use in interpreting fluvial successions and in reservoir engineering studies. Channel dimensions need to be scaled correctly to produce meaningful experimental stratigraphy. In particular, any vertical distortion of the channels modifies the resultant stratigraphical and sedimentological architecture, as exemplified by the dependence of the transverse bed and stratigraphical architecture predictors on channel depth. The transverse bed slope of the experimental lateral accretion surfaces has similar values as the targeted natural prototype rivers and agrees well with theory. Also, the formation of experimental stratigraphy for meandering rivers depends on the deepest channel cuts and the order of occurrence of these channel cuts, which is consistent with the prediction from theory. Three key archimetric (i.e. quantitative, non-dimensional, architectural dimensions) parameters are identified to enhance the three-dimensional characterization of the external geometry and internal stratigraphy of meander belts. First, meander belt width-to-thickness ratios are generally between 100 and 200, which is consistent with reported values of natural meander belts. Second, the internal stratigraphical architecture of meander belts largely consists of fragmented deposits: 95% of the stratigraphic sets are thinner than the mean channel. Third, prediction of the slope of lateral accretion deposits is possible based on the mean channel depth, a typical grain size and channel curvature. This indicates that a few fairly basic morphological (i.e. channel) and sedimentary parameters provide insightful quantitative predictors for the three-dimensional sedimentary architecture of meander belts, which is complementary to well and seismic observations. Most fluvial systems are subject to changes in forcing. For example, aggradation rates and discharge are extremely variable. This thesis demonstrates that moderate floods (≈50 years recurrence time) and aggradation rates (
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